scholarly journals Effect of feed type and other factors on soluble microbial product production and its disinfection byproduct formation during biological treatment of wastewater organics

2016 ◽  
Vol 17 (2) ◽  
pp. 399-406 ◽  
Author(s):  
Jinlin Liu ◽  
Xiaoyan Li ◽  
Anjie Li
Keyword(s):  
Biological Treatment ◽  
Volatile Fatty Acids ◽  
Standard Procedure ◽  
Influential Factors ◽  
Treated Wastewater ◽  
Organic Substrates ◽  
Disinfection Byproduct ◽  
Organic Carbon Concentration ◽  
Wide Range ◽  
Byproduct Formation

Soluble microbial products (SMPs) can act as a disinfection byproduct (DBP) precursor besides natural organic matter (NOM) when source water is polluted by biologically treated wastewater effluent that has SMPs as its main component. Influential factors of SMPs as a DBP precursor were investigated in this study. Model feed substrates were biologically incubated to simulate the biological treatment of wastewater organics, and the SMPs produced were chlorinated according to the standard procedure to study the DBP formation potential (DBPFP) of SMPs. Feed chemical type is a crucial factor affecting SMP production and the following DBP formation. SMPs from four kinds of model feed substrates with the same initial organic carbon concentration produced DBPs with a wide range from 196 to 684 μg L−1 and also different DBP formation properties. Different organic substrates would facilitate the growth of different microbial species, which produce SMPs with varied levels and chemical structure and subsequently different DBP formation characters. For the environmental factors, an anaerobic condition showed a significant effect, producing extremely high chloral hydrate up to about 2000 μg L−1, probably due to the production of volatile fatty acids. Different incubation conditions can not only bring about different levels of SMPs and DBPs, but also SMPs with different DBP formation feathers.

scholarly journals Biotechnology for Gas-to-Liquid (GTL) Wastewater Treatment: A Review

Water ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2126
Author(s):  
Riham Surkatti ◽  
Muftah H. El-Naas ◽  
Mark C. M. Van Loosdrecht ◽  
Abdelbaki Benamor ◽  
Fatima Al-Naemi ◽  
...  
Keyword(s):  
Biological Treatment ◽  
Volatile Fatty Acids ◽  
Human Life ◽  
Cell Immobilization ◽  
Oxygen Demand ◽  
Environmental Benefits ◽  
Aerobic Biodegradation ◽  
Treated Wastewater ◽  
Treatment Methods ◽  
Gas To Liquid

Gas-to-liquid (GTL) technology involves the conversion of natural gas into several liquid hydrocarbon products. The Fischer–Tropsch (F–T) process is the most widely applied approach for GTL, and it is the main source of wastewater in the GTL process. The wastewater is generally characterized by high chemical oxygen demand (COD) and total organic carbon (TOC) content due to the presence of alcohol, ketones and organic acids. The discharge of this highly contaminated wastewater without prior treatment can cause adverse effects on human life and aquatic systems. This review examines aerobic and anaerobic biological treatment methods that have been shown to reduce the concentration of COD and organic compounds in wastewater. Advanced biological treatment methods, such as cell immobilization and application of nanotechnology are also evaluated. The removal of alcohol and volatile fatty acids (VFA) from GTL wastewater can be achieved successfully under anaerobic conditions. However, the combination of anaerobic systems with aerobic biodegradation processes or chemical treatment processes can be a viable technology for the treatment of highly contaminated GTL wastewater with high COD concentration. The ultimate goal is to have treated wastewater that has good enough quality to be reused in the GTL process, which could lead to cost reduction and environmental benefits.

Making Swimming Pools Safer: Does Copper–Silver Ionization with Chlorine Lower the Toxicity and Disinfection Byproduct Formation?

2021 ◽  
Vol 55 (5) ◽  
pp. 2908-2918
Author(s):  
Joshua M. Allen ◽  
Michael J. Plewa ◽  
Elizabeth D. Wagner ◽  
Xiao Wei ◽  
Gretchen E. Bollar ◽  
...  
Keyword(s):  
Swimming Pools ◽  
Disinfection Byproduct ◽  
Byproduct Formation

Iodinated disinfection byproduct formation in a MnO2/I−/EPS system

Chemosphere ◽  
2021 ◽  
pp. 130643
Author(s):  
Lingxiao Fu ◽  
Xiaofeng Wu ◽  
Yongbin Zhu ◽  
Lei Yao ◽  
Chengqiang Wu ◽  
...  
Keyword(s):  
Disinfection Byproduct ◽  
Byproduct Formation

scholarly journals Responses to Ecopollutants and Pathogenization Risks of Saprotrophic Rhodococcus Species

Pathogens ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 974
Author(s):  
Irina B. Ivshina ◽  
Maria S. Kuyukina ◽  
Anastasiia V. Krivoruchko ◽  
Elena A. Tyumina
Keyword(s):  
Survival Strategies ◽  
Complex Life Cycle ◽  
Anthropogenic Pressure ◽  
Resting Cells ◽  
Organic Substrates ◽  
Negative Effects ◽  
Anthropogenic Pollutants ◽  
Rhodococcus Species ◽  
Wide Range ◽  
Rigid Cell Wall

Under conditions of increasing environmental pollution, true saprophytes are capable of changing their survival strategies and demonstrating certain pathogenicity factors. Actinobacteria of the genus Rhodococcus, typical soil and aquatic biotope inhabitants, are characterized by high ecological plasticity and a wide range of oxidized organic substrates, including hydrocarbons and their derivatives. Their cell adaptations, such as the ability of adhering and colonizing surfaces, a complex life cycle, formation of resting cells and capsule-like structures, diauxotrophy, and a rigid cell wall, developed against the negative effects of anthropogenic pollutants are discussed and the risks of possible pathogenization of free-living saprotrophic Rhodococcus species are proposed. Due to universal adaptation features, Rhodococcus species are among the candidates, if further anthropogenic pressure increases, to move into the group of potentially pathogenic organisms with “unprofessional” parasitism, and to join an expanding list of infectious agents as facultative or occasional parasites.

Volatile fatty acids production from biowaste at mechanical-biological treatment plants: Focusing on fermentation temperature

2020 ◽  
Vol 314 ◽  
pp. 123729 ◽  
Author(s):  
David Fernández-Domínguez ◽  
Sergi Astals ◽  
Miriam Peces ◽  
Nicola Frison ◽  
David Bolzonella ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Biological Treatment ◽  
Volatile Fatty Acids ◽  
Fermentation Temperature

The chemistry of stabilized clusters

1982 ◽  
Vol 308 (1501) ◽  
pp. 27-34 ◽  
Keyword(s):  
Electron Donor ◽  
Organic Molecules ◽  
Metal Cluster ◽  
Organic Substrates ◽  
Insertion Reactions ◽  
Donor Ligand ◽  
Small Organic Molecules ◽  
Wide Range ◽  
Metal Metal ◽  
High Yields

Studies of the chemistry of metal cluster complexes and, in particular, their reactions with small organic molecules, have been confined to relatively few systems. Among the reasons for this are: (i) not many clusters are easily synthesized in high yields; (ii) their reactions often give a multitude of products that are difficult to separate and characterize; (iii) the conditions required to bring about reactions often lead to fragmentation of the cluster into lower nuclearity (often mononuclear) species. One cluster whose chemistry has been extensively studied is [Os 3 H 2 (CO) 10 ]. This can be synthesized in high yields from [Os 3 (CO) 12 ] + H 2 (Knox et al. 1975) and reacts readily under mild conditions with a wide range of electron-donor molecules by virtue of its coordinative unsaturation (Shapley et al. 1975; Deeming & Hasso 1976; Adams & Golembeski 1979). Formally, one may consider that a metal—metal double bond is present, which is reduced to a single bond on coordination of an additional two-electron donor ligand such as an organophosphine. The presence of metal—hydrogen bonds in this cluster and the cluster’s ability to coordinate organic substrates enable it to undergo a wide variety of insertion reactions, leading to products that may be regarded as intermediates in the reduction of organic molecules by clusters (Deeming & Hasso 1975; Keister & Shapley 1975).

scholarly journals Gradient HPLC in the determination of drug lipophilicity and acidity

2001 ◽  
Vol 73 (9) ◽  
pp. 1465-1475 ◽  
Author(s):  
Roman Kaliszan ◽  
Piotr Haber ◽  
Tomasz Baczek ◽  
Danuta Siluk
Keyword(s):  
Mobile Phase ◽  
High Performance ◽  
Standard Procedure ◽  
Gradient Elution ◽  
Log P ◽  
Retention Data ◽  
Organic Modifier ◽  
Wide Range ◽  
Aqueous Component ◽  
Initial Ph

The linear-solvent strength (LSS) model of gradient elution in high-performance liquid chromatography (HPLC) has been demonstrated to provide parameters of lipophilicity and acidity of analytes. pKa and log kw values are determined in three gradient runs. The first two experiments use an aqueous buffered eluent with a wide-range organic modifier gradient at pH of buffer, providing suppression of ionization of the analyte. That experiment allows an estimate of contents of the organic modifier in the mobile phase (%B), producing requested retention coefficient, k, for the nonionized form of the analyte. The next experiment is carried out with the latter %B and a pH-gradient of the aqueous component of the eluent that is sufficient to overlap possible pKa value of the analyte. The initial pH of the buffer used to make the mobile phase is selected to insure that the analyte is in nonionized form. The resulting retention time allows an estimate of pKa in a solvent of the given %B.The log kw parameter obtained correlated well with the corresponding value obtained by the standard procedure of extrapolation of retention data determined in a series of isocratic measurements. The correlation between log kw and the reference parameter of lipophilicity, log P, was very good for a series of test analytes. The values of pKa were found to correlate with the literature pKa data determined in water for a set of aniline derivatives studied.

scholarly journals Newly discovered Asgard archaea Hermodarchaeota potentially degrade alkanes and aromatics via alkyl/benzyl-succinate synthase and benzoyl-CoA pathway

2021 ◽  
Author(s):  
Jia-Wei Zhang ◽  
Hong-Po Dong ◽  
Li-Jun Hou ◽  
Yang Liu ◽  
Ya-Fei Ou ◽  
...  
Keyword(s):  
Nitrate Reduction ◽  
Coenzyme A ◽  
Organic Substrates ◽  
Mangrove Sediments ◽  
Sulfate Reducing ◽  
Sequence Read Archive ◽  
Wide Range ◽  
Genes Encoding ◽  
Sediment Carbon ◽  
Reducing Bacteria

AbstractAsgard archaea are widely distributed in anaerobic environments. Previous studies revealed the potential capability of Asgard archaea to utilize various organic substrates including proteins, carbohydrates, fatty acids, amino acids and hydrocarbons, suggesting that Asgard archaea play an important role in sediment carbon cycling. Here, we describe a previously unrecognized archaeal phylum, Hermodarchaeota, affiliated with the Asgard superphylum. The genomes of these archaea were recovered from metagenomes generated from mangrove sediments, and were found to encode alkyl/benzyl-succinate synthases and their activating enzymes that are similar to those identified in alkane-degrading sulfate-reducing bacteria. Hermodarchaeota also encode enzymes potentially involved in alkyl-coenzyme A and benzoyl-coenzyme A oxidation, the Wood–Ljungdahl pathway and nitrate reduction. These results indicate that members of this phylum have the potential to strictly anaerobically degrade alkanes and aromatic compounds, coupling the reduction of nitrate. By screening Sequence Read Archive, additional genes encoding 16S rRNA and alkyl/benzyl-succinate synthases analogous to those in Hermodarchaeota were identified in metagenomic datasets from a wide range of marine and freshwater sediments. These findings suggest that Asgard archaea capable of degrading alkanes and aromatics via formation of alkyl/benzyl-substituted succinates are ubiquitous in sediments.

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